It's nothing too bad. To make a vague analogy, let's say my friend and I were talking about Pokémon in a group chat, and then someone interjected that they don't like Pokémon. That's fine, but then they tried to convince us that Pokémon is bad, as if our enjoyment of a franchise invalidated their opinion of the game.

And then the entire chat got wrapped up into the conversation, and then it completely diverged into something nasty. It was quite unfortunate.